The "key part" of the plan by Mr Jabour and Mr Scanlan was to bring government policy into line with the wishes of the leaseholders, counsel assisting the commission Ben Katekar said.

This was denied by Mr Jabour when he gave evidence on Wednesday.

Damian Obeid took the stand after a series of abusive emails between him and Mr Jabour was tabled.

Damian Obeid called his cousin a "c***sucker" and a "half-wit" and said he "did nothing to get it through", which referred to a change in government policy where direct negotiations would be held with leaseholders in place of a public tender.

Mr Jabour responded by calling Mr Obeid "fatboy."

Mr Obeid denied it was his family's political connections that forced the changes they wanted, but rather the "exceptional" lobbying of Mr Scanlan during several years of discussions between lessees and government.

"How you `got it through' was, I suggest, by using influence within the department," counsel assisting the commission Ian Temby said.

"No, that's not correct," Damian Obeid replied.

It was also revealed that Eddie Obeid and his wife were paid in bundles of cash from the takings of the Circular Quay properties, which earned the family about $2.5 million annually.

The Obeids' interest in the properties was hidden to protect themselves against media scrutiny, Damian Obeid said.

This was because the family felt like targets after Eddie Obeid won a defamation action against The ABC and The Sydney Morning Herald, he said.

He denied that part of the intention was to hide the fact his father had extensive and expanding business interests.

The inquiry heard that Mrs Obeid was for several years paid a "housekeeping fee" of $1000 per week from takings at the cafe and restaurants.

Mrs Obeid was paid because the properties had been purchased with money borrowed against her home, Damian Obeid said.

He denied claims made by business associate Paul Maroon that Eddie Obeid also received payments.